Well-Aligned, Vertically Al-Doped ZnO Nanowires Synthesized on ZnO:Ga∕Glass Templates

High-density, single-crystal, vertically aligned, Al-doped ZnO nanowires with an Al content of 1.05 atom % were synthesized on templates at 550°C. Although introducing Al did not change the physical dimensions of the ZnO nanowires, the lattice constant increased by 0.25% and the optical properties of the ZnO nanowires were degraded. However, the experimental results also showed that the threshold emission field can be significantly decreased from 16 to , and the work function, ϕ, can also be reduced from 5.3 to 3.39 eV by introducing Al atoms into the ZnO nanowires.